Reasons for Test

Differentiate between true muscle weakness and limitations due to pain

Determine if muscles
and nerves
are working properly

Distinguish between muscle and nerve disorders

Possible Complications

Problems from the procedure are rare, but all procedures have some risk. Your doctor will review potential problems, like:

Bleeding

Pain or bruising at the needle insertion site

Infection at the needle insertion site

What to Expect

Prior to Test

Make sure you talk to your doctor about the medications you are taking. You may be asked to adjust certain medications up to 1 week before the test.

On the day before and day of the test:

If you have
myasthenia gravis, ask if you should take any medication before the test.

If directed to, avoid cigarettes, coffee, tea, and soft drinks for 2-3 hours before the test.

Take a bath or shower before the test.

On the day before, do not use lotion or oil.

Wear comfortable clothing. You will have to change into a hospital gown.

Tell your doctor if you have a pacemaker or other implanted device.

Remove any clothing, jewelry, hairpins, eyeglasses, hearing aids, or other metal objects that may interfere with the procedure.

Description of the Test

A small needle electrode will be inserted into a muscle at rest. You will be asked to rest or contract the muscle. The electrical activity picked up by the needle will produce a waveform. The waveform will be recorded and analyzed. The test is repeated on different muscles and limbs.

After Test

You will be able to leave after the test is done. When you are home:

Resume any medications you stopped before the test

Resume normal activities as tolerated

How Long Will It Take?

30-90 minutes

Will It Hurt?

You may have some pain when the needle electrodes are inserted. The insertion feels like an injection into the muscle.

After the test, you may have muscle aches and discomfort for several days. Warm compresses and pain medication may help.

Results

The doctor doing the EMG may discuss the results with you. A report will also be sent to your personal doctor. Your doctor will discuss treatment options based on the tests and other factors.

Revision Information

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.